Recently, as the lack of an energy resource such as petroleum or coal is expected, the interest in the substitute energy has been more increased. In this regard, a solar cell converting solar energy into electrical energy has been spotlighted.
A solar cell (or photovoltaic cell) is a core element in solar power generation to directly convert solar light into electricity.
For example, if the solar light having energy greater than band-gap energy of a semiconductor is incident into a solar cell having the P-N junction structure of a semiconductor, electron-hole pairs are generated. As electrons and holes are collected into an N layer and a P layer, respectively, due to the electric field formed in a PN junction part, photovoltage is generated between the N and P layers. In this case, if a load is connected to electrodes provided at both ends of the solar cell, current flows through the solar cell.
The current generated from the solar cell is transferred to a junction box through a bus bar. In general, the bus bar is formed on the front surface of a solar cell panel and extends to a rear surface of the solar cell panel through a hole formed in the solar cell panel to allow the current to flow into the junction box.
However, since the hole is formed in the panel, the durability and reliability of the panel are deteriorated. As the size of the panel is enlarged, the problems become serious.
In this regard, there has been suggested a method of increasing the thickness of a solar cell panel to prevent the panel from being bent or damaged, but this method may cause the increase in the weight of the solar cell panel and make the process complex.
Therefore, there is a need to provide a solar cell module having a new structure capable of improving the durability and reliability of a solar cell panel when a bus bar is formed on the solar cell panel.